Multicell area paging for cellular telecommunications system

ABSTRACT

A radio access network portion of a telecommunications network ( 18 ) which serves a mobile station (MS) is connecting to a core network. The radio access network portion has plural base stations (BS) serving respective plural cells (C), as well as plural control nodes (RNCs). The control nodes include a first control node (RNC 1 ) for controlling a first group of the plural base stations and a second control node (RNC 2 ) for controlling a second group of the plural base stations. A multicell area (MCA) includes cells served by at least some of the first group of base stations and cells served by at least some of the second group of base stations. The radio access network portion of a telecommunications network further has a paging control node which stores information regarding the multicell area. To page the mobile station in the multicell area, the paging control node (1) sends paging messages to each of the base stations serving the multicell area controlled by the paging control node: and (2) sends a paging message to any other control nodes which control base stations serving cells in the multicell area. The paging control node determines to which base stations and other control node(s) it should send paging messages by consulting a paging table ( 100 ). Preferably the paging control node is one of the control nodes of the radio access network. The paging control node is connected to the other control node(s) by an inter-control node link ( 32 ) over which the paging message is sent.

[0001] This patent application is related to U.S. patent applicationSer. No. 09/035,788 filed Mar. 6, 1998 and entitled “TelecommunicationsInter-Exchange Congestion Control”; U.S. patent application Ser. No.09/035,821 filed Mar. 6, 1998 and entitled “TelecommunicationsInter-Exchange Measurement Transfer”; and U.S. patent application Ser.No. 09/______, (attorney docket: 34648-404 USPT) filed Mar. 6, 1998 andentitled “System and Method used in a Mobile Telecommunications Networkfor Load Balancing Ongoing Calls between Different Base Station”, all ofwhich are incorporated herein by reference.

BACKGROUND

[0002] 1. Field of the Invention

[0003] The present invention pertains to telecommunications, andparticularly to paging of a mobile station within a cellulartelecommunications system.

[0004] 2. Related Art and Other Considerations

[0005] In recent years cellular telephones have become increasinglypopular. A cellular telephone is just one example of what is referred toin telephone parlance as a “mobile station” or “mobile terminal”.Telecommunications services are provided between a cellulartelecommunications network and a mobile station (e.g. cellulartelephone) over an air interface, e.g. over radio frequencies. At anymoment an active mobile station is communicating over the air interfacewith one or more base stations. The base stations are. in turn. managedby base station controllers (BSCs), which in some systems are also knownas radio network controllers (RNCs). The radio network controllers areconnected via control nodes to a core telecommunications network.Examples of control nodes include a mobile switching center (MSC) nodefor connecting to connection-oriented, circuit switched networks such asPSTN and/or ISDN, and a general packet radio service (e.g., GPRS) nodefor connecting to packet-switched networks such as Internet, forexample.

[0006] The radio transmissions of each base station cover a particulargeographical area. As used herein. the geographical area into whichradio transmissions of a base station extend is termed a “cell”. Suchdefinition of “cell” thus encompasses systems in which the perspectiveis such that a base station covers a single cell, as well as systemswherein the term “cell” is differently employed in a manner such that abase station serves more than one cell. Regardless of perspective, ahandoff or handover must occur as a mobile station travels from an oldcell to a new cell (e.g., for example when the mobile travels into acell covered by different base stations and or different RNCs). Thispermits mobile stations to “roam” considerable distances.

[0007] In view of the extent to which a mobile station can travel,location management of a mobile telecommunications system can beextensive. A number of geographical area levels can be utilized. In thisregard. cells can be grouped into larger areas. for example intolocation areas. A location area can be served by plural radio networkcontrollers (RNCs). Location areas are discussed, for example. in U.S.patent application Ser. No. 08/916.285, filed Aug. 22. 1997, entitled“GEOGRAPHICAL RESTRICTION IN CELLULAR TELECOMMUNICATIONS NETWORK”, whichis incorporated herein by reference. In view e.g., of the potentialcomplexity of such location management schemes, an effort is made tokeep track of the location of the mobile station while trying tominimize the radio resources devoted to such effort.

[0008] One method for saving radio resources involves location updatingmessaging. In location updating, when a mobile station which is idle(i.e., there is no current connection between the mobile station and thenetwork) moves into a cell belonging to a new location area, the mobilestation apprises of its whereabouts by sending a message known as alocation update. The location update message must be sent so that both ahome location register (HLR) maintained for the mobile station and avisitor location register (VLR) have appropriate current informationabout the mobile station and its whereabouts. Then, when the networkneeds to establish a connection or exchange data with the mobilestation, the mobile station is paged within the last location areaapprised by the mobile station. The mobile station answers the page bysending a page response message to the network from the cell where themobile station is currently located.

[0009] As indicated above, the aforementioned location updating isutilized when the mobile station is idle (e.g., is not participating inan on-going call). Moreover, when the mobile station is idle thelocation updating is applicable not only to circuit switched services(which can involve speech services and/or data services), but also topacket switched services as well. Whereas in circuit switched servicesthe data user has radio resources continuously reserved for theconnection to the radio network during a data call (e.g., even when nottransferring data), in packet switched services the user has radioresources reserved for the connection to the radio network only wheneither (1) the mobile station desires to transmit or (2) the network hassomething to transmit to the mobile station. In other words, in thepacket switched service the mobile station (e.g., a computer with mobiletermination) does not have radio resources reserved for the connectionto the network constantly while the computer is in use, but only duringthese two transmission events. One example of packet switched servicerecently available within the GSM (Global System for Mobilecommunications) system is General Packet Radio Service (GPRS).

[0010] When a mobile station is connected with the network during aconnection involving a packet-switching service, procedures such as cellupdating and routing area updating are employed. When the mobile stationmoves into a new cell, it updates the network with its location on acell level. However, in periods of no data transfer, cell updatingwastes radio resources. Instead routing area updating is used in periodsof no data transfer. Thus, the routing area updating typically occursonly during the lifetime of the packet-switched connection. A routingarea is a group of cells. The routing area is typically smaller than alocation area. Since traffic for a packet switched service is verybursty in nature with long periods of no packet transfer, it would be awaste of radio resources to have a radio channel continuously assignedto a connection. Instead, when the mobile station moves into a newrouting area, the mobile station updates the network with its currentlocation, e.g., with its current routing area, similar to the locationarea update described above. When a packet is to be sent from thenetwork to the mobile station, and when the location of the mobilestation is known only at the routing area level, a paging message issent in all cells belonging to the routing area where the mobile madeits last routing area update.

[0011] Location areas and routing areas although generally havingdiffering purposes, are hereinafter referred to as multicell areas. Acell can be included in more than multicell area. Two or more multicellareas that contain such a cell are said to be “overlapping”. The use ofoverlapping multicell areas can limit the “ping-pong” effect at bordersbetween exchanges (e.g., as between mobile switching centers (MSCs). Theping-pong effect occurs when a mobile station repeatedly crosses betweentwo cells which belong to different multicell areas. When the ping-pongeffect is present, the mobile station must update its multicell areawith each such crossing. Moreover, ping-pong effects generate muchundesirable additional signaling within the network, e.g. between MSCs.

[0012] In current cellular telecommunications systems, distribution ofpaging is handled in a truly hierarchial manner. In this regard, an MSCdistributes a page to all RNCs that control cells within the area wherethe mobile station is to be paged (e.g. a location area or a routingarea). The RNCs then send each page request to all base stationstransmitting and receiving radio signals which (1) are controlled by theRNC; and (2) are located within the area where the mobile station is tobe paged (e.g., a location area or a routing area). The base stationsthen send the actual paging signal over the air interface.

[0013] Certain paging procedures are accommodated within the GSM (GlobalSystem for Mobile communications). For example, GSM 09.02 Version 5.8.0,February 1998, GSM MAP specification, Chapters 6.2.1-6.2.2, Paging andSearch, cater to the possibility for a VLR to request paging from anMSC. As ascertained from this specification, the VLR knows the locationarea where the mobile station is supposedly located, and forms pagingsignals which are to be sent to the BSCs. However, the MSC and the VLRhave a one-to-one relationship; i.e., there is one VLR for each MSC. TheMSC and VLR are also two differing node types, representing differingfunctionality types.

[0014] GSM also allows for a Serving GPRS Support Node (SGSN) to receivea paging request from the MSC/VLR. An SGSN is a type of MSC handlingonly packet switched services, and has a different functionality thanthe MSC/VLR. In the SGSN, the routing area where the mobile station islocated is stored in case the mobile station is attached to the GPRSservice (mentioned above). See GSM 03.60, GPRS Service Description,Chapter 6.3, Interactions Between SGSN and MSC/VLR.

[0015] In the Pacific Digital Cellular standard for inter-MSC paging,appearing in document TTC JJ-70.10 chapter 3.3.1.2 (1995), pagingdistribution is accomplished by an anchor mobile switching center (AMSC)from which the terminating call was routed to other MSCs. Thus, thisstandard involves the core network in paging distribution (being at theMSC level), and requires that the core network have knowledge of thecell topology.

[0016] It may, in some instances, be desirable to have atelecommunications network with a strict functional division between a“core network” (to which the MSC belongs) and the radio access network(which includes the RNCs). According to this strict functional division,the radio access network would handle all radio related operations (forexample, the knowledge of which base stations, cells, and channels areto be used to obtain radio coverage and capacity within a certaingeographical area). In other words, the core network (specificallyincluding the MSC) would not have knowledge regarding cell structure,and more specifically would not know what particular cells form a givenlocation area.

[0017] In a cellular network having the strict functional divisiondescribed above, a problem would occur when the core network needs topage a mobile station that is idle. The page should be sent to all cellswithin the location area. However, the core network (e.g., the MSC) doesnot know to which RFNCs the page should be sent.

[0018] A similar problem can exist for a mobile station having a packetswitched connection. There is no continuously reserved radio resourcefor the packet switched connection. Instead, the connection ismaintained by using routing area updating. That is, the mobile stationsends a routing area update message to the network when the mobilestation comes into a new routing area. The identity of the routing areawhere the mobile station is currently located is stored in the RNC whichcontrols the connection to the mobile station, known as the Serving RNCor SRNC. For limiting the above-described ping-pong effect, the mobilestation's routing area may also include cells that are controlled byRNCs other than the RNC which is currently in control of the packetswitched connection to the mobile station (i.e. other than the SRNC).The problem arises when the MSC is to send a packet to the mobilestation. and therefore a need to page the mobile station from the basestations for each cell belonging to the routing area. In other words.somehow a page needs to be sent by RNCs other than the Serving RNC. Yet,with strict functional division, the MSC has no knowledge of the plan ofthe radio access network and thus no knowledge of which RNCs should beinvolved in paging the mobile station.

[0019] What is needed therefore, and an object of the present invention,is a technique for paging a mobile station in a multicell area,particularly when the core network does not know from which nodes apaging message should be issued.

BRIEF SUMMARY OF THE INVENTION

[0020] A radio access network portion of a telecommunications networkwhich serves a mobile station is connecting to a core network. The radioaccess network portion has plural base stations serving respectiveplural cells, as well as plural control nodes. The control nodes includea first control node for controlling a first group of the plural basestations and a second control node for controlling a second group of theplural base stations. In a multi-group, multicell context, a multicellarea includes cells served by at least some of the first group of basestations and cells served by at least some of the second group of basestations. The radio access network portion of a telecommunicationsnetwork further has a paging control node which stores informationregarding the multicell area.

[0021] In one mode of the invention. the multicell area is a locationarea comprising plural cells. In this first mode. the core networkhandles locating updating and paging initiation for the location area.The location updating of the first mode occurs. for example, between thecore network and the mobile station when the mobile station is idle, andunder such circumstances works essentially the same for bothcircuit-switched services and packet-switched services.

[0022] In another mode of the invention in which the mobile stationsubscribes to a packet switched service and updating occurs during aconnection, the multicell area is a routing area comprising pluralcells. The radio access network handles routing area updating and paginginitiation for the routing area.

[0023] In either the location area (first) or routing area (second)modes, when the mobile station is paged in the multicell area. thepaging control node (1) sends paging messages to each of the basestations serving the multicell area controlled by the paging controlnode; and (2) sends a paging message to any other control nodes whichcontrol base stations serving cells in the multicell area. The pagingcontrol node determines to which base stations and other control node(s)it should send paging messages by consulting a paging table. When theother control node(s) receive the paging message, those other controlnode(s) consult a MAP Native Cell Constituency Table to determine whichbase stations served thereby comprises multicell area, i.e., to whichbase stations the paging message should be sent.

[0024] Preferably the paging control node is one of the control nodes ofthe radio access network. The paging control node is connected to theother control node(s) by an inter-control node link. The paging messageis sent from the paging control node to the second control node over theinter-control node link.

[0025] A response to the paging message can trigger a moveover of aserving radio network controller designation from one RNC node toanother RNC node. For example, the paging control node of the presentinvention can initiate moveover of a serving radio network controller tofrom one RNC node to another RNC node. The moveover of the serving radionetwork controller can occur during either the first mode or the secondmode.

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The foregoing and other objects, features, and advantages of theinvention will be apparent from the following more particulardescription of preferred embodiments as illustrated in the accompanyingdrawings in which reference characters refer to the same partsthroughout the various views. The drawings are not necessarily to scale,emphasis instead being placed upon illustrating the principles of theinvention.

[0027]FIG. 1 is a schematic view of a telecommunications networkaccording to a first mode of the invention showing e.g., variouspaging-related events therefor.

[0028]FIG. 1A, FIG. 1B, and FIG. 1C are schematic views of atelecommunications network respective SRNC moveover scenarios.

[0029]FIG. 2 is a schematic view of a telecommunications networkaccording to a second mode of the invention showing e.g., variouspaging-related events therefor.

[0030]FIG. 3A is a schematic view of an example radio network controller(RNC) which operates as a paging control node in accordance with a modeof the present invention.

[0031]FIG. 3B is a schematic view of an example radio network controller(RNC) which does not operates as a paging control node but whichnevertheless controls cells in a multicell area for which a pagingcontrol node receives a paging message from a core network.

[0032]FIG. 4A is a diagrammatic view of an example format for a pagingmessage sent over an Inter-RNC transport link from the radio networkcontroller of FIG. 3A to the radio network controller of FIG. 3B.

[0033]FIG. 4B is a diagrammatic view of an example format for a pagingresponse message sent over an Inter-RNC transport link from the radionetwork controller of FIG. 3B to the radio network controller of FIG.3A.

[0034]FIG. 5 is a flowchart showing basic steps performed at a pagingcontrol node in one illustrative mode of a paging technique utilized inthe network of FIG. 1.

[0035]FIG. 6 is a flowchart showing basic steps performed at a radionetwork controller (RNC) (not serving as a paging control node) in oneillustrative mode of the paging technique of FIG. 5.

[0036]FIG. 7 is a schematic view showing overlapping and layering ofmulticell areas.

DETAILED DESCRIPTION OF THE DRAWINGS

[0037] In the following description, for purposes of explanation and notlimitation, specific details are set forth such as particulararchitectures, interfaces. techniques, etc. in order to provide athorough understanding of the present invention. However, it will beapparent to those skilled in the art that the present invention may bepracticed in other embodiments that depart from these specific details.In other instances, detailed descriptions of well known devices,circuits, and methods are omitted so as not to obscure the descriptionof the present invention with unnecessary detail.

[0038]FIG. 1 shows a telecommunications network 18 which includes both acore network and a radio access network. In FIG. 1, the core network isshown above broken line 20; the radio access network is shown below line20. The core network includes mobile switching center (MSC) 19. As shownin FIG. 1, mobile switching center (MSC) 19 is connected to one or morecontrol nodes of radio access network, and particularly to radio networkcontroller 22 ₁ (RNC1) and radio network controller 22 ₂ (RNC2). Suchconnection between mobile switching center (MSC) 19 and radio networkcontroller (RNC1) 22 ₁ is provided by terrestrial link 26 ₁; theconnection between mobile switching center (MSC) 19 and radio networkcontroller (RNC2) 22 ₁ is provided by terrestrial link 26 ₂.

[0039] Radio network controller (RNC1) 22 ₁ controls a first group ofbase stations comprising the radio access network, particularly basestations BS_(x,y) of FIG. 1 for which x=2. The base stations BS_(2,y)comprising the first group serve a respective first group of cellsC_(x,y) for which x=1. Similarly, radio network controller (RNC2) 22 ₂controls a second group of base stations comprising the radio accessnetwork. particularly base stations BS_(x,y) of FIG. 1 for which x =2.The base stations BS_(x,y) comprising the second group serve arespective first group of cells C_(x,y) for which x =2.

[0040] Certain cells of FIG. 1 are included in what is herein referencedas a “multicell area” or “MCA”. In particular, the cells C in FIG. 1having both rising and falling cross hatching comprise the multicellarea. In other words, cells C_(1.3) through C_(1.8) served by radionetwork controller (RNC1) 22₁ and cells C_(2.0) through C_(2.5) servedby radio network controller (RNC2) 22₂ form the multicell area. Thus, asused herein, a multicell area or MCA is an area comprising plural cellsand requiring service by more than one radio network controller (RNC) inorder for all cells to be served by at least one RNC. The base stations(BS) of the cells comprising the multicell area are shown in FIG. 1 asbeing connected by terrestrial links to the particular RNC whichcontrols the respective base stations. Although not illustrated, itshould be understood that comparable terrestrial links are also providedfor other base stations not included in the multicell area but alsocontrolled by these RNCs.

[0041] The multicell area can be any level of cell organizationsuperceding that of the basis cell. Examples of a multicell area are alocation area and a routing area, as discussed in more detail below.

[0042] An Inter-RNC transport link 32, also known as the Inter-RNC link,connects radio network controller (RNC1) 22 ₁ and radio networkcontroller (RNC2) 22 ₂ Ordinarily, the inter-RNC transport link 32facilitates, e.g., the inter-RNC soft-handovers. In this regard,Inter-RNC transport link 32 is utilized for the transport of control anddata signals between radio network controller (RNC1) 22 ₁ and radionetwork controller (RNC2) 22 ₂. Inter-RNC transport link 32 can beeither a direct link or a logical link as described, for example, inInternational Application Number PCT/US94/12419 (InternationalPublication Number WO 95/15665). The Inter-RNC transport link 32 can govia a transport network and/or a signalling network and/or the corenetwork.

[0043] A particular feature of the present invention is furtheremployment of Inter-RNC transport link 32 for conveying paginginformation between RNCs. Such employment is in addition to other usesof Inter-RNC transport link 32, such as carrying cell conditioninformation (e.g., from cells which neighbor the cell where the call issetup) or congestion messages for use in network decision making (suchas call admission and call congestion control) [see U.S. patentapplication Ser. No. 09/035,788 filed Mar. 6, 1998 and entitled“Telecommunications Inter-Exchange Congestion Control”; U.S. patentapplication Ser. No. 09/035.821 (attorney docket: 2380-44) filed Mar. 6,1998 and entitled “Telecommunications Inter-Exchange MeasurementTransfer ”; and U.S. patent application Ser. No. 09/ _, (attorneydocket: 34648-404 USPT) filed Mar. 6, 1998 and entitled “System andMethod used in a Mobile Telecommunications Network for Load BalancingOngoing Calls between Different Base Station”, all of which areincorporated herein by reference].

[0044] In accordance with the present invention, the radio accessnetwork includes a paging control node. In the example of theillustrated embodiment herein discussed. the paging control node is oneof the RNCs, particularly radio network controller (RNC1) 22 ₁. Asdescribed below in connection with FIG. 3A, the paging control node ofthe present invention includes a paging control node paging table 100which is simulated. as hereinafter described, by TABLE 1 hereof.

[0045] An example configuration of radio network controller (RNC1) 22 ₁is shown in FIG. 3A for one particular type of radio access network. Theradio network controller (RNC1) 22 ₁ includes a switch 240. Switch 240,which is controlled by RNC control unit 242, has a plurality of ports.some of which are connected to diversity handover unit (DHU) 230 andothers of which are connected to various interfaces. Diversity handoverunit (DHU) 230 is connected to a timing unit 241. The RNC control unit242 is connected to each element of RNC 22 ₁. RNC 22 ₁ is connected to asignaling network via a signaling interface 243. Signaling interface 243is connected to RNC control unit 242. The interfaces connected to portsof switch 240 include MSC interface unit 244; RNC interface unit 246;and base station interface units 248. MSC interface unit 244 isconnected to the appropriate mobile switching center 19. RNC interfaceunit 246 is connected to inter-RNC transport link 32. Base stationinterface units 248 are connected to the group of base stations (BS)served by the RNC 22 ₁. TABLE 1 Number of cells in List of cells MCA inMCA Number of List of other controlled controlled other RNCs RNCs Nameof by paging by paging controlling controlling multicell control controlcells in this cells in this Layer of area (MCA) node node MCA MCA thisMCA MCA A 6 C_(1,3); C_(1,4;) 1 RNC 22₂ 1 C_(1,5); C_(1,6;) C_(1,7);C_(1,8) MCA B — — — — 1 — — — — — — MCA J — — — — —

[0046] In the example of FIG. 3A, the paging control node paging table100 is stored in RNC control unit 242. As shown in TABLE 1 , the pagingcontrol node paging table 100 includes a list of multicell areas, withmulticell areas MCA-A through MCA-J being shown in TABLE 1 . TABLE 1 hasa column for the name of the multicell area, with each row of TABLE 1corresponding to a particular named multicell area. The second column ofTABLE 1 has a value indicative of the number of cells in MCA controlledby the paging control node; the third column of TABLE 1 includes a listof cells in MCA controlled by the paging control node; the fourth columnof TABLE 1 has a value indicative of the number of number of RNCs (otherthan the paging control node) which controls cells in the MCA; the fifthcolumn of TABLE 1 includes a list of the other RNCs controlling cells inthis MCA. The sixth column of TABLE 1 identifies the layer to which theMCA belongs (the concept of “layer” is subsequently discussed withreference to TABLE 2 and FIG. 7).

[0047] TABLE 1 shows details only for MCA A, which is the particularmulticell area illustrated in FIG. 1. It should be understood thatdetailed information is also typically included in such table for anyother multicell areas for which radio network controller (RNC1) 22 ₁serves as a paging control node.

[0048] The structure of radio network controller (RNC2) 22 ₂ , i.e., theRNC of FIG. 1 which in the present example does not serve as the pagingcontrol node, is shown in FIG. 3B. The structure and configuration ofradio network controller (RNC2) 22 ₂ of FIG. 3B is essentially the sameas that of radio network controller (RNC1) 22 ₁ of FIG. 3A, for whichreason identical reference numerals are employed in FIG. 3A and FIG. 3Bfor comparable elements. However, since radio network controller (RNC2)22 ₂ is not a paging control node, the RNC control unit 242 of radionetwork controller (RNC2) 22 ₂ does not include paging control nodepaging table 100. Rather, RNC control unit 242 of radio networkcontroller (RNC2) 22 ₂ has another table, herein known as the MAP NativeCell Constituency Table 102.

[0049] An example MAP Native Cell Constituency Table 102 is illustratedin TABLE 2 hereof. For the particular example of TABLE 2 hereindiscussed, MAP Native Cell Constituency Table 102 indicates that radionetwork controller (RNC2) 22 ₂ is serving four distinct multicell areas,particularly MCA-A, MCA-B, MCA-K, and MCA-L. For each MCA, TABLE 2 liststhe identity of the paging control node (second column of TABLE 2 ); thenumber of cells in the MCA controlled by radio network controller (RNC2)22 ₂ (third column of TABLE 2 ); the list of cells in the MCA controlledby radio network controller (RNC2) 22 ₂ (fourth column of TABLE 2 ); andthe layer in which the MCA resides (fifth column of TABLE 2 ). It shouldagain be understood that, although information is provided in TABLE 2primarily only for multicell area MCA-A, detailed information is alsotypically included in such table for any other multicell areas havingcells controlled by radio network controller (RNC2) 22 ₂ . TABLE 2 MAPNATIVE CELL CONSTITUENCY TABLE IDENTITY NUMBER OF LIST OF OF CELLS INCELLS IN PAGING THIS MCA THIS MCA CONTROL CON- CON- LAYER MCA NODE FORTROLLED TROLLED OF THIS NAME THIS MCA BY THIS RNC BY THIS RNC MCA MCA-ARNC 22₁ 6 C_(2,0); C_(2,1); 1 C_(2,2); C_(2,3); C_(2,4); C_(2,5); . . .MCA-B . . . . . . . . . 1 MCA-K . . . . . . C_(2,3); C_(2,4); 2 C_(2,5);C_(2,6); C_(2,7); C_(2,8); MCA-L . . . . . . . . . 2

[0050] The layer column of Table 2 is explained with reference to FIG.7. FIG. 7 shows the four multicell areas MCA-A, MCA-B, MCA-K, and MCA-Lserved, at least in part by radio network controller (RNC2) 22 ₂ . Asshown. MCA-A is partially served by radio network controller (RNC2) 22 ₂(another portion of MCA-A being served by radio network controller(RNC1) 22 ₁). As set forth in TABLE 2. radio network controller (RNC2)22 ₂ maintains layers of multicell areas. in particular level 1 andlayer 2 as shown in FIG. 7. In the situation illustrated in FIG. 7,multicell area MCA-A and multicell area MCA-B are on layer 1, whilemulticell area MCA-K and multicell area MCA-L are on layer 2.

[0051] Thus, radio network controller (RNC2) 22 ₂ associates eachmulticell area with a layer of multicell areas maintained by radionetwork controller (RNC2) 22 ₂. This layer designation is particularlyimportant in the case of overlapping multicell areas. FIG. 7 shows thatmulticell area MCA-A and multicell area MCA-K overlap in an overlap areaOA-Q. The importance of the layer designation stems from the fact that.in the paging message, the mobile station MS can be identified by atemporary mobile station identifier (TMSI) with respect to the multicellarea in which it currently resides. The assignment of a TMSI for amobile station MS with respect to a multicell area is complicated by thefact that another multicell area may use the same TMSI for anothermobile station. In other words, differing multicell areas may beingusing the same TIMSIs for differing mobiles.

[0052] In view of the foregoing, it should be understood that two mobilestations with the same TMSI, but belonging to differing multicell areas(MCA-A and MCA-K), may be in overlap area OA-Q at the same time. If apaging message is issued with respect to cells in multicell area MCA-A,without information more than the TMSI of the paged mobile station, itmay occur that both mobile stations would respond. However, in thepresent invention, upon receipt of a paging message from radio networkcontroller (RNC1) 22 ₁ relative to multicell area MCA-A and prior tosending the paging message of event 6-3, radio network controller (RNC2)22 ₂ determines that multicell area MCA-A is in layer 1. Therefore,radio network controller (RNC2) 22 ₂ includes the layer designation inthe paging message. The other mobile in the overlap area OA-Q, althoughrecognizing the same TMSI, knows from the layer parameter that thepaging message is intended for multicell area MCA-A rather thanmulticell area MCA-K, and therefore does not respond. Only the mobilestation MS to which the paging message is intended responds, despitepossible double assignment of TMSI values within the overlap area OV-Q.

[0053] Thus, in one aspect of the invention involving multicell areas,each MCA is assigned to a multicell area (MCA) layer. The assignment ofa MCA layer parameter can be performed by the paging control node. Thecells of each RNC involved in the paging for the multicell area are sentpaging messages which contain the MCA layer parameter. For this reason,both TABLE 1 (for radio network controller (RNC1) 22 ₁ ) and TABLE 2(FOR radio network controller (RNC2) 22 ₂ ) includes MCA layerparameters. Also, the paging messages can include MCA layer parameters.

[0054] Insofar as multicell area layers are concerned, the mobilestation MS must also be made aware of which layer it is registered in orbelongs to. Informing the mobile station MS of multicell area layer canbe accomplished in the locating updating and/or routing area updatingprocedures. For example, the multicell area layer parameter can beprovided directly in a location registration response message orimplicitly by allowing the mobile station MS and network to select aspecific multicell area (with its corresponding multicell area layerparameter) which is published as the “registration multicell area”broadcasted in system information in the cell where the mobile stationMS is registering.

[0055] In one scenario of the multicell area layering of the presentinvention, a multicell area has the same multicell area layer parameterfor all RNCs having cells belonging to the multicell area. In anotherscenario, on the other hand, a multicell area is viewed at differingRNCs as having a differing multicell area layer parameter. In this otherscenario, the network publishes all multicell area information(including multicell area layer parameters) in broadcasted systeminformation in each cell. When paging the mobile station MS , each cellpaging message contains the multicell area layer parameter of the pagedmobile station MS as published for each specific cell. This otherscenario essentially moves the multicell area layer parameter to a celllevel, and obviates the MCA layer parameters in TABLE 1 and TABLE 2.

[0056] An example of a first mode of operation of the present inventionis illustrated with respect to FIG. 1; an example of operation of asecond mode is illustrated with respect to FIG. 2. In this first mode,the core network handles locating updating and paging initiation for thelocation area. The location updating of the first mode occurs, forexample, between the core network and the mobile station when the mobilestation is idle, and under such circumstances works essentially the samefor both circuit-switched services and packet-switched services. Thesecond mode of the invention is applicable when the mobile station has apacket-switched connection, with the multicell area being a routing areacomprising plural cells. In the second mode, the radio access networkhandles routing area updating and paging initiation for the routingarea.

[0057] General events involved in both the first mode and the secondmode are generically illustrated in FIG. 5 and FIG. 6. FIG. 5 basicallyshows events performed by radio network controller (RNC1) 22 ₁ (whichfunctions as the paging control node in the illustrated embodiment),while FIG. 6 basically shows events performed by radio networkcontroller (RNC2) 22 ₂.

[0058]FIG. 5 shows, as event 5-1, the paging control node, particularlyradio network controller (RNC1) 22 ₁,receiving a paging message. In themode of the invention pertaining to location areas, the paging messagefor the mobile station is initiated by the core network, particularlymobile switching center (MSC) 19 in the manner shown by event 5-1 inFIG. 1. Event 5-1 in FIG. 1 is thus reception of a CN-RAN pagingmessage, i.e., core network-radio access network paging message. On theother hand, in the second mode of the invention pertaining to packetswitched services, the page can be initiated by a radio networkcontroller, e.g., radio network controller (RNC1) 22 ₁,as shown by event5-1 in FIG. 2.

[0059] Regarding the CN-RAN paging message of event 5-1 illustrated inFIG. 1, mobile station MS has previously send a location update orcomparable message to the core network. On the basis of the update, thehome location register (HLR) for the mobile station MS points to theappropriate visiting location register (VLR). The visiting locationregister (VLR) knows the current multicell area MCA-A for the mobilestation MS, and forwards this information to the mobile switching center(MSC) 19. The page to the mobile switching center (MSC) 19 from thevisiting location register (VLR) carries the current multicell areaMCA-A for the mobile station MS. Commonly the mobile switching center(MSC) 19 and visiting location register (VLR) are collocated in the samenode (denoted MSC/VLR). Mobile switching center (MSC) 19 then consults atable to determine which RNC serves as the paging control node for themulticell area in which mobile station MS was last located. In theparticular example of FIG. 1, such paging control node is radio networkcontroller (RNC1) 22₁, so that the paging message of event 5-1 is sentto radio network controller (RNC1) 22 ₁. The paging message of event 5-1includes an indentifier of the multicell area in which mobile station MSwas last located.

[0060] Upon receipt of the event 5-1 paging message, as event 5 -2 thepaging control node (i.e., radio network controller (RNC1) 22 ₁) checksits paging table 100 to determine to which cells controlled by thepaging control node a paging message should be issued. In the exampleunder discussion, the paging control node checks TABLE 1 to determinewhich cells controlled by radio network controller (RNC1) 22 ₁ are to bepaged. From TABLE 1 the radio network controller (RNC1) 22 ₁ obtains theidentity of such cells, using the multicell area identifier (MCA-A) tolocate the proper row of TABLE 1. The identity of the cells to which apaging message is to be sent is gleaned from the third column ofTABLE 1. As event 5-3, the paging control node sends the paging messageto the base stations for the cells belonging to the multicell area whichare controlled by the paging control node.

[0061] As event 5-4, the paging control node also determines whether themulticell area identified by the paging message of event 5-1 includescells which are controlled by RNCs other than the paging control node.Such is the case for the example of FIG. 1, since radio networkcontroller (RNC2) 22₂ controls the second group of cells (i.e. cellsC_(2.0) through C_(2.5)) comprising multicell area MCA-A.

[0062] In the case in which the multicell area identified by the pagingmessage of event 5-1 includes cells which are controlled by RNCs otherthan the paging control node, the paging control node (i.e., radionetwork controller (RNC1) 22 ₁ sends a paging message on Inter-RNCtransport link 32 to such other RNCs as event 5-6.

[0063] An example format for the paging message sent on Inter-RNCtransport link 32 to such other RNCs as event 5-6 is shown in FIG. 4A.The paging message of event 5-6 includes a header 4A-1 which identifiesthe node to which the paging message is destined, e.g., radio networkcontroller (RNC2) 22 ₂ . In addition, the paging message of event 5-6specifies (as field 4A-2) the identity of paging control node from whichthe paging message originated, as well (as field 4A-3) an identificationof the multicell area for which the page is issued. In addition, thepaging message of event 5-6 includes typical paging information(indicated by field 4A-4) including the identity of the mobile stationMS being paged. In the situation of layering of multicell areas as abovediscussed with respect to FIG. 7, the paging message of FIG. 4A can alsoinclude a field 4A-5 specifying the multicell area layer parameter (asassigned, e.g., by the paging control node).

[0064] Event 5-5 shows the paging control node awaiting a pagingresponse. The paging response may come from one of the cells controlledby radio network controller (RNC1) 22 ₁ in response to the pagingmessage(s) sent at event 5-3. Alternatively, as described in more detailin connection with FIG. 6, the paging control node may receive thepaging response over Inter-RNC transport link 32 from another RNC, e.g.,radio network controller (RNC2) 22 ₂, in response to the paging messagesent as event 5-6. It should be understood that reception of a pagingresponse can occur at any time after event 5-3, and that a time outperiod is preferably established within which a paging response messagemust be received.

[0065]FIG. 6 shows events performed by the other RNC, e.g., the radionetwork controller (RNC2) 22 ₂ , upon receipt of the paging message ofevent 5-6 of FIG. 5. The paging message of event 5-6 , also known as theInter-RNC paging message, is received over Inter-RNC transport link 32.Upon receiving the paging message of event 5-6 over Inter-RNC transportlink 32 (event 6-1). as event 6-2 the radio network controller (RNC2) 22₂ consults its MAP Native Cell Constituency Table 102 (see FIG. 3B andTABLE 2). The check of event 6-2 is for determining what cellscontrolled by radio network controller (RNC2) 22 ₂ belong to themulticell area identified by the paging message of event 5-6 . After thecheck of event 6-2, as event 6-3 the radio network controller (RNC2) 22₂ sends the paging message to the cells controlled thereby in suchmulticell area as a RNC-BS paging message.

[0066] As shown in FIG. 1. it so happens that mobile station MS residesin C_(2.0) at the time that the paging messages of event 6-3 aretransmitted. The mobile station MS in cell C_(2.0) receives a page overthe interface from base station BS_(2.0). In response to the pagemessage received over the air interface, mobile station MS returns overthe air interface to base station BS_(2.0) a paging response message(MS-BS paging response message). As shown by event 6-4, base stationBS_(2.0) forwards the paging response message (BS-RNC paging responsemessage) to radio network controller (RNC2) 22 ₂. Upon receipt of thepaging response message of event 6-4, as event 6-5 the radio networkcontroller (RNC2) 22 ₂ sends a paging response message (Inter-RNC pagingresponse message) over Inter-RNC transport link 32 to the paging controlnode, i.e., to radio network controller (RNC1) 22 ₁. Upon receipt of thepaging response message of event 6-5, the radio network controller(RNC1) 22 ₁ functions to make the connection between the calling partyfrom the core network and mobile station MS.

[0067] An example format for the paging response message sent onInter-RNC transport link 32 from radio network controller (RNC2) 22 ₂ toradio network controller (RNC1) 22 ₁ as event 6-5 is shown in FIG. 4B.The paging response message of event 6-5 includes a header 4B-1 whichidentifies the node to which the paging response message is destined,e.g., radio network controller (RNC1) 22 ₁. In addition, the pagingresponse message of event 6-5 specifies (as field 4B-2) the identity ofpaging control node from which the paging response message originated,as well (as field 4B-3) an identification of the multicell area forwhich the page was issued. In addition, the paging response message ofevent 6-5 includes (as field 4B-4) typical paging response informationincluding the identity of the mobile station being page. In thesituation of layering of multicell areas as above discussed with respectto FIG. 7, the paging response message of FIG. 4B can also include afield 4B-5 specifying the multicell area layer parameter.

[0068] In FIG. 5, for sake of simplicity, events 5-6 has been shown tooccur subsequent to earlier numbered events such as event 5-3. Such neednot necessarily be the case, however, as the events occurring withrespect to the cells controlled by RNC 22 ₂ can be timed to occur inanother manner, such as essentially contemporaneously with the paging inthe cells controlled by RNC 22 ₁, for example.

[0069] In the foregoing description, the mobile switching center (MSC)22 need only store the address of one RNC for each location area, whichis the paging control node for that location area. Preferably suchpaging control node RNC has cells within that location area. The page isthen sent to the paging control node, which has the knowledge (viapaging control node paging table 100) of (1) which cells under itscontrol are part of the location area, and (2) which other RNCs (if any)have cells within that location area. Thus, the paging control RNC,which received the paging message from mobile switching center (MSC) 22,distributes the page to (1) all base stations under its controlcorresponding to cells in the location area, and over Inter-RNCtransport link 32 to (2) all other RNCs that have cells within thelocation area. Each of the other RNCs know which cells under theircontrol are part of the location area (see e.g., MAP Native CellConstituency Table 102). These other RNCs distribute the paging messageto cells which they control which are part of the location area.

[0070] In context of a packet switched connection, a page can beinitiated by an RNC, e.g., as shown by radio network controller (RNC1)22 ₁ and event 5-1 in FIG. 2. In this second mode of the invention, themulticell area can be a routing area. In other respects, events of thesecond mode in FIG. 2 are essentially the same as above described withrespect to the first mode and FIG. 1.

[0071] In general, for each mobile station MS having a connection to theradio access network, there is an RNC which serves as a Serving RNC(SRNC). The Serving RNC (SRNC) handles the connection between the mobilestation MS and the radio access network as well as the connection to thecore network. The SRNC stores the location of the mobile station MS, andin the case of a packet-switched connection, particularly stores therouting area of the mobile station MS

[0072] The present invention also involves, for both the mode of FIG. 1and FIG. 2, initiation of a SRNC moveover procedure in connection withthe paging. Three differing scenarios of SRNC moveover procedure areillustrated with respect to FIG. 1A, FIG. 1B, and FIG. 1C, respectively.

[0073] Each of the three scenarios of SRNC moveover follow (e.g., occursubsequently) various events described in FIG. 5 and FIG. 6. In thisregard, in the general manner of FIG. 5, the paging control node (e.g.,a SRNC) sends the page request to all RNCs that have cells within therouting area, including the base stations controlled by the SRNC thatinitiated the page. The page utilizes the Inter-RNC transport link 32.The other RNCs then distribute the page to the cells, as in the mannerdescribed in connection with FIG. 6. In the three scenarios of SRNCmoveover illustrated, radio network controller (RNC1) 22 ₁ is theServing RNC (SRNC) for the particular mobile station MS. Both radionetwork controller (RNC1) 22 ₁ and radio network controller (RNC2) 22 ₂distribute base station paging messages to all base stationscorresponding to cells in the routing area. The base stations furthersend paging messages on the paging channels over the air interface tothe respective cells. The mobile station MS answers in one of the cells.Upon answering, a paging response message is received at an RNC.

[0074] In the three SRNC moveover scenarios, it is assumed that the RNCwhich receives the paging response from the mobile station MS is otherthan the SRNC (i.e., the RNC which initiated the paging distribution).

[0075] In the first scenario of SRNC moveover illustrated in FIG. 1A,radio is network controller (RNC1) 22 ₁ initiates moveover of theServing RNC (SRNC) functionality (e.g., handling of the connectionbetween the mobile station MS and the radio access network as well asthe connection to the core network). That is, the Serving RNC (SRNC),e.g., radio network controller (RNC1) 22 ₁ (also serving as the pagingcontrol node) has determined from event 6-5 that another RNC (e.g.,radio network controller (RNC2) 22 ₂ ) has received the paging responsemessage from mobile station MS. Upon completion of the SRNC moveover,that radio network controller (RNC2) 22 ₂ [rather than radio networkcontroller (RNC1) 22 ₁ ] is considered as the Serving RNC (SRNC) for themobile station MS. In the scenario of FIG. 1A, the paging responsemessage is be sent back over Inter-RNC transport link 32 to the SRNC(i.e., radio network controller (RNC1) 22₁ ) as event 6-5 in the mannerpreviously described.

[0076] In the SRNC moveover scenario of FIG. 1A, after event 6-5 thepaging control node (radio network controller (RNC1) 22 ₁) sends an SRNCmoveover request message via mobile switching center (MSC) 19 to thecore network, as indicated by event 1A-1. The SRNC moveover requestmessage of event 1A-1 indicates both the identity of the mobile stationMS, as well as the address of the RNC which will serve as the newServing RNC (SRNC) for the mobile station MS (e.g., radio networkcontroller (RNC2) 22 ₂).

[0077] Upon receipt of the SRNC moveover request message of event 1A-1,the core network contacts the new Serving RNC (SRNC) [e.g. radio networkcontroller (RNC2) 22₂] as event 1A-2. In response to the contact ofevent 1A-2, radio network controller (RNC2) 22₂ can send the pagingresponse message from mobile station MS directly to the core network asshown by event 1A-3. The connection between the core network and the newServing RNC (SRNC) (i.e. radio network controller (RNC2) 22₂) is thusestablished.

[0078] In the foregoing first SRNC moveover scenario, it should beunderstood that the SRNC moveover request message sent from radionetwork controller (RNC1)22₁ to the core network can include, or beaccompanied by, the paging response message from the mobile station MS(since the paging response message was received by radio networkcontroller (RNC 1)22₁ over Inter-RNC transport link 32 as event 5-6 ).

[0079] In the second SRNC moveover scenario, the RNC which received thepaging response message from the mobile station MS, i.e., radio networkcontroller (RNC2)22₂ sends the paging response message directly to thecore network (i.e., to MSC 19) as event 1B-1 without involving thepaging control node (i.e., radio network controller (RNC1) 22 ₁). Thus,in the second SRNC moveover scenario, event 6-5 does not occur. Rather,forwarding of the paging response message from radio network controller(RNC2) 22 ₂ to the core network prompts the core network to change toradio network controller (RNC2) 22 ₂ as the SRNC for the mobile station.When the former SRNC (i.e., radio network controller (RNC1) 22 ₁ timesout after sending the paging message with no response), so that nofurther activity is conducted at radio network controller (RNC1) 22 ₁regarding the paging of mobile station MS.

[0080] In the third SRNC moveover scenario (see FIG. 1C) resembles thesecond scenario, with the RNC which received the paging response messagefrom the mobile station MS sending the paging response message directlyto the core network (i.e., to MSC 19) as event 1B-1 without involvingthe paging control node (i.e. radio network controller (RNC1) 22 ₁). Inaddition, in the third SRNC moveover scenario of FIG. 1C the new SRNC(i.e., radio network controller (RNC2) 22 ₂) sends an advisory messageto the paging control node (i.e., the former SRNC, radio networkcontroller (RNC1) 22 ₁) informing that the mobile station MS hasresponded.

[0081] Although the foregoing three scenarios of SRNC moveover have beendescribed only in the context of the first mode (which involves locationarea), it should be understood that the three scenarios are equallyapplicable to the second mode (which involves routing area). In thesecond mode, the paging is initiated by the RAN (as above describedrelative to event 5-1′ of FIG. 2) rather than by the core network.Moreover, in the second mode of the invention, the paging response isnot returned to the core network as in the case of the first mode.

[0082] It should be understood that SRNC moveover can be prompted forreasons other than those described above. For example, SRNC moveover maybe initiated for reasons such as routing area updating, cell updating,and diversity handling, e.g., soft handover (macrodiversitysplitting/combining) [see U.S. patent application Ser. No. 08/980,013filed Nov. 26, 1997 and entitled “Diversity Handling Moveover for CDMAMobile Telecommunications”, which is incorporated herein by reference].

[0083] The present invention allows for location areas and routing areasto cover more than one RNC. Moreover. advantageously, the core networkneed not know the internal configuration of the radio access networkrespecting location area or routing area, thereby permitting strictfunctional division between the core network and the radio accessnetwork. In other words, the paging distribution of the presentinvention is accomplished totally within the radio access network, andthus is hidden from the core network.

[0084] Moreover, overlapping location areas and routing areas (asdescribed in FIG. 7) are possible, with the such overlapping topologybeing hidden from and not affecting the core network. Thus, overlappingmulticell areas can be introduced in the radio access network withoutsignificantly affecting the core network. In this regard, for aGSM-based core network, this is particularly advantageous since onlyminor modifications are needed in the core network.

[0085] The foregoing has described a radio access network having twoRNCs, with each RNC controlling nine base stations, and with a multicellarea comprising twelve cells (six of which are controlled by radionetwork controller (RNC1) 22 ₁ and six of which are controlled by radionetwork controller (RNC2) 22_(2 ). It should be understood that the foregoing network topology is merely one example, and that other network topologies are encompassed by the present invention. In this regard, the parameters of the foregoing are not critical. For example, the number of RNCs can vary, as well as the number of base stations controlled by each RNC. Furthermore, the number of cells comprising the multicell area will vary for each implementation, as well as the association of constituent cells of the multicell area to RNCs. It should readily be recognized that an multicell area may be served by more than two RNCs. in which case the paging control node (e.g., radio network controller (RNC1) 22)₁ in the illustrated example) will send the paging message of event 5-6to such other RNCs as well.

[0086] In the illustrated embodiment, the paging control node wasselected to be one of the RNCs, particularly radio network controller(RNC1) 22 ₁. The person skilled in the art should understand that thepaging control node can instead be another RNC, or even vet a non-RNCnode. For example, the paging control node may be a specialized nodewhich serves one of the RNCs of radio access network. Further, thepaging control node may serve several RNCs.

[0087] It should also be understood that the configuration of radionetwork controller (RNC1) 22 ₁ as shown in FIG. 3 is but oneillustrative example, and that other configurations can be utilizedconsistently with the present invention. Moreover, whereas in FIG. 3paging control node paging table 100 has been included in RNC controlunit 242, it should be appreciated that paging control node paging table100 can be situated elsewhere.

[0088] While the invention has been described in connection with what ispresently considered to be the most practical and preferred embodiment,it is to be understood that the invention is not to be limited to thedisclosed embodiment, but on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the appended claims.

What is claimed is: _
 1. A radio access network portion of atelecommunications network, the radio access network being connecting toa core network and serving a mobile station, the radio access networkportion comprising: plural base stations serving respective pluralcells; plural control nodes including a first control node forcontrolling a first group of the plural base stations and a secondcontrol node for controlling a second group of the plural base stations;wherein a multicell area includes cells served by at least some of thefirst group of base stations and cells served by at least some of thesecond group of base stations; a paging control node which storesinformation regarding the multicell area whereby, when the mobilestation is paged in the multicell area, the paging control node sends apaging message to at least one of the control nodes which controls basestations serving cells in the multicell area.
 2. The network of claim 1,wherein the control node to which the paging control node sends a pagingmessage stores a list of cells controlled thereby and which are includedin the multicell area.
 3. The network of claim 1, wherein the controlnode to which the paging control node sends a paging message transmitsto at least portions of plural multicell areas, wherein each of theplural multicell areas is assigned a layer parameter, and wherein thelayer parameter is transmitted with the paging message to the cells onthe list.
 4. The network of claim 3, wherein the layer parameter isassigned to a multicell area by the paging control node, wherein thefirst control node and the second control node are connected by aninter-control node link, and wherein the layer parameter is transmittedover the inter-control node link.
 5. The network of claim 1, wherein thepaging control node is one of the control nodes.
 6. The network of claim1, wherein the first control node and the second control node areconnected by an inter-control node link, and wherein the paging messageis sent from the first control node to the second control node over theinter-control node link.
 7. The network of claim 1, wherein a page ofthe mobile station is initiated by the core network and wherein themulticell area is a location area comprising plural cells.
 8. Thenetwork of claim 1, wherein the mobile station subscribes to a packetswitched service, wherein a page of the mobile station is initiated bythe radio access network, and wherein the multicell area is a routingarea.
 9. The network of claim 1, wherein the core network does not knowhow the multicell area is defined.
 10. The network of claim 1, whereinthe page is from the core network and is initiated by a mobile switchingcenter, and wherein the page includes an indication of the multicellarea for the mobile station.
 11. A radio access network portion of atelecommunications network, the radio access network being connecting toa core network and serving a mobile station, the radio access networkportion comprising: plural base stations serving respective pluralcells; a first radio network control node for controlling a first groupof the plural base stations; a second radio network control node forcontrolling a second group of the plural base stations; wherein amulticell area includes cells served by at least some of the first groupof base stations and cells served by at least some of the second groupof base stations; wherein, to page the mobile station in the multicellarea, the first radio network control node issues a paging message (1)to those base stations in the first group belonging to the multicellarea and (2) to the second radio network control node.
 12. The networkof claim 11, wherein the second radio network control node maintains alist of cells controlled thereby and which are included in the multicellarea, and wherein the second radio network control node sends a pagingmessage to the cells on the list.
 13. The network of claim 11, whereinthe second radio network control node sends a paging message transmitsto at least portions of plural multicell areas, wherein each of theplural multicell areas is assigned a layer parameter, and wherein thelayer parameter transmitted with the paging message to the cells on thelist.
 14. The network of claim 11, wherein the first radio networkcontrol node and the second radio network control node are connected byan inter-radio network control node link, and wherein the paging messageis sent from the first radio network control node to the second radionetwork control node over the inter-radio network control node link. 15.The network of claim 11, wherein a page of the mobile station isinitiated by the core network and wherein the multicell area is alocation area comprising plural cells.
 16. The network of claim 11,wherein the mobile station subscribes to a packet switched service,wherein a page of the mobile station is initiated by the radio accessnetwork, and wherein the multicell area is a routing area.
 17. Thenetwork of claim 11, wherein the core network does not know how themulticell area is defined.
 18. The network of claim 11, wherein the pageis from the core network and is initiated by a mobile switching center,and wherein the page includes an indication of the multicell area forthe mobile station.
 19. The network of claim 11, wherein when a pagingresponse message responsive to the paging message is received from thesecond radio network control node, the first radio network control nodeissues a moveover request message to the core network for changingcontrol of the connection with the mobile station from the first radionetwork control node to the second radio network control node.
 20. Thenetwork of claim
 19. wherein after the core network changes control ofthe connection with the mobile station from the first radio networkcontrol node to the second radio network control node, the second radionetwork control node sends the paging response message to the corenetwork.
 21. A radio access network portion of a telecommunicationsnetwork, the radio access network being connecting to a core network andserving a mobile station, the radio access network comprising: pluralbase stations serving respective plural cells; a first radio networkcontrol node for controlling a first group of the plural base stations;a second radio network control node for controlling a second group ofthe plural base stations; an inter-radio network control link connectingthe first radio network control node and the second radio networkcontrol node, and wherein the inter-radio network control link carriesat least one of a (1) paging message and (2) a response to a pagingmessage.
 22. The network of claim 21, wherein a multicell area includescells served by at least some of the first group of base stations andcells served by at least some of the second group of base stations; andwherein, when the core network desires to page the mobile station in themulticell area, the first radio network control node issues a pagingmessage (A) to those base stations in the first group belonging to themulticell area and (B) to the second radio network control node, thepaging message (B) being carried over the inter-radio network controllink.
 23. The network of claim 21, wherein the second radio networkcontrol node maintains a list of cells controlled thereby and which areincluded in the multicell area, and wherein the second radio networkcontrol node sends a paging message to the cells on the list.
 24. Thenetwork of claim 21, wherein the second radio network control node sendsa paging message transmits to at least portions of plural multicellareas, wherein each of the plural multicell areas is assigned a layerparameter, and wherein the layer parameter transmitted with the pagingmessage to the cells on the list.
 25. The network of claim 21, whereinwhen the response to a paging message is received from the second radionetwork control node, the first radio network control node issues amoveover request message to the core network for changing control of theconnection with the mobile station from the first radio network controlnode to the second radio network control node.
 26. The network of claim25. wherein after the core network changes control of the connectionwith the mobile station from the first radio network control node to thesecond radio network control node, the second radio network control nodesends the response to the paging message to the core network.
 27. Amethod of operating a telecommunications network which comprises a radioaccess network being connected to a core network, the radio accessnetwork including plural base stations serving respective plural cellsand plural control nodes including a first control node for controllinga first group of the plural base stations and a second control node forcontrolling a second group of the plural base stations; the methodcomprising: receiving a paging message at a paging control node of theradio access network, the paging message referring to a multicell area.the multicell area including cells served by at least some of a firstgroup of base stations and cells served by at least some of a secondgroup of base stations; using the paging control node to send a pagingmessage to at least one of the control nodes which controls basestations serving cells in the multicell area.
 28. The method of claim27, further comprising: storing at the control node to which the pagingcontrol node sends a paging message a list of cells controlled therebyand which are included in the multicell area; transmitting the pagingmessage from the control node to which the paging control node sends thepaging message to base stations serving the cells on the list.
 29. Themethod of claim 28, wherein the control node to which the paging controlnode sends the paging message transmits to at least portions of pluralmulticell areas, and wherein the method further comprises: assigning toeach of the plural multicell areas is assigned a layer parameter, andtransmitting the layer parameter with the paging message to the basestations serving the cells on the list.
 30. The method of claim 27,wherein the paging control node is one of the control nodes.
 31. Themethod of claim 27, wherein the plural control nodes include a firstcontrol node and a second control node. and wherein the paging controlnode is one of the first radio network control node and the second radionetwork control node.
 32. The method of claim 31, wherein the firstcontrol node and the second control node are connected by aninter-control node link, and wherein the paging message is sent from thefirst control node to the second control node over the inter-controlnode link.
 33. The method of claim
 27. further comprising initiating apage of the mobile station by the core network, and wherein themulticell area is a location area comprising plural cells.
 34. Themethod of claim 27, wherein the mobile station subscribes to a packetswitched service, wherein a page of the mobile station is initiated bythe radio access network, and wherein the multicell area is a routingarea.
 35. The method of claim 27, wherein the core network does not knowhow the multicell area is defined.
 36. The method of claim 27, furthercomprising initiating the page from the core network, and furthercomprising including in the page an indication of the multicell area forthe mobile station.
 37. The method of claim 27, further comprisingreturning a paging response message from the at least one of the controlnodes to the paging control node.
 38. The method of claim 37, furthercomprising, when the paging response message is received, issuing fromthe paging node a moveover request message to the core network forchanging control of the connection with the mobile station from thepaging control node to the one of the at least one of the control nodesto which the mobile station responded.
 39. The method of claim 38,wherein after the core network changes control of the connection withthe mobile station, the one of the at least one of the control nodes towhich the mobile station responded sends the paging response message tothe core network.
 40. A method of operating a telecommunications networkwhich comprises a radio access network being connected to a corenetwork, the radio access network including plural base stations servingrespective plural cells and plural control nodes including a firstcontrol node for controlling a first group of the plural base stationsand a second control node for controlling a second group of the pluralbase stations; one of the plural control nodes initially handling aconnection between the core network and a mobile station engaged in apacket switched service, the method comprising: receiving a pagingmessage for the mobile station at a paging control node of the radioaccess network, the paging message referring to a multicell area, themulticell area including cells served by at least some of a first groupof base stations and cells served by at least some of a second group ofbase stations; using the paging control node to send a paging message toat least one of the control nodes which controls base stations servingcells in the multicell area; and upon receiving a paging responsemessage from the mobile station, initiating at the paging control node arequest to move handling of the connection between the core network anda mobile station to another control node.
 41. The method of claim 40,wherein after the core network moves control of the connection with themobile station, the control nodes newly handling the connection sendsthe paging response message to the core network.
 42. A method ofoperating a radio access network portion of a telecommunicationsnetwork. the radio access network being connecting to a core network andserving a mobile station. the radio access network portion comprisingplural base stations serving respective plural cells and a radio networkcontrol node for controlling the plural base stations, the methodcomprising: defining, with respect to the plural cells, a firstmulticell area and a second multicell area; associating, at the radionetwork control node, a first layer parameter with the first multicellarea and a second layer parameter with the second multicell area;sending from the radio network control node a paging message withrespect to a paged mobile station, the paging message including both amobile station identifier and a layer parameter appropriate for themobile station.
 43. A radio access network portion of atelecommunications network, the radio access network being connecting toa core network and serving a mobile station, the radio access networkportion comprising: plural base stations serving respective pluralcells; a first radio network control node for controlling a first groupof the plural base stations; a second radio network control node forcontrolling a second group of the plural base stations; wherein a firstmulticell area includes cells served by at least some of the first groupof base stations and cells served by at least some of the second groupof base stations; wherein a second multicell area includes cells servedby the second group of base stations; wherein, to page the mobilestation in the multicell area, the first radio network control nodeissues a paging message including a temporary mobile station identifier[TMSI] (1) to those base stations in the first group belonging to themulticell area and (2) to the second radio network control node; andwherein, the second radio network control node assigns to each of theplural multicell areas a multicell area layer parameter, and wherein themulticell area layer parameter is transmitted with the paging message tothe cells on the list.